DEPOSITS IS THE BRISTOL DISTRICT. 



77 



the sides and interstices of the deposit yielded me part of a fish- 

 palate, which is probably of Carboniferous-limestone age, and great 

 numbers of Encrinital stems, a comparatively recent freshwater 

 operculum, and numerous examples of Tubutella. Whatever may be 

 the age of this deposit, groups of the latter are usually surrounded 

 by an irony matrix which seems part thereof. 



Vein at Ashton. — On the west side of the Avon, about a mile 

 beyond Ashton, considerable deposits of iron-ore occur ; but I have 

 been unable to examine them. They lie at the foot of the lime- 

 stone escarpment. On the tableland above them, at Longwood 

 Farm there are disturbed Carboniferous Limestones, in which a 

 vein occurs containing occasional lumps of galena and some ca- 

 lamine. Tubutella is present in great abundance. The upper 

 part of this vein is somewhat honeycombed ; and the tubes are 

 found adhering to thin flakes of calc-spar. Xo other organisms 

 were found at this spot. 



Wesibury-on-Trym — Carboniferous Limestone with Minerals and 

 Oolitic Remains. — On passing from the Durdham-Down quarries 

 (previously mentioned) along the eastern edge of the Carboniferous 

 Limestone, at a distance of two miles, some large quarries are to be 

 found, On the eastern side of one at Southmead, worked by Mr. 

 Kennedy, there maybe seen what appears to be an ordinary mineral 

 vein, about a foot thick, passing down through the section. It con- 

 tains good haematite iron-ore, ochre, galena, and calamine. Although 

 it appeared nothing but a mass of mineral matter, I still hoped a 

 sample might yield some evidence of its age. In this I succeeded 

 beyond my expectation ; for on washing it I at once found many 

 angular pieces of Inferior Oolite, which, from their being stained 

 with iron, were not before visible. On a still closer examination 

 I obtained the oolitic organisms given in the list below, asso- 

 ciated with Tubutella ; the specimens show very little sign of 

 attrition. No Oolitic deposit from which they could be derived, 

 however, is in this district nearer than Dundry, six miles to the 

 south, or the Cotteswolds, many miles to the east, with, in the latter 

 case, the area of the Bristol coal-field intervening. 



In the same quarry there is at another spot a pocket of light- 

 green clay. Although very intractable, I was able to disintegrate 

 it sufficiently to find that it contained Algae &c. ; and although 

 there remains a little doubt as to their age, it is likely they are of 

 comparatively recent date. 



^estbury vein, Oolitic Organisms. 



Fish-tooth, 



Nerinsea. 



Solarium. 



Univalve, sp. 



Turbo. 



Dentalium. 



Astarte, 



Cardium. 



Ostrea. 



Thecidium. 



Bryozoa, several species. 



Echini, teeth, plates, and spines, 



Entomostraca. 



Serpuke. 



Eoraminifera ? 



Tubutella, 



Pentacrinite joints. 



Encrinite stems, Carboniferous. 



Algge (in clay vein), several genera 



